hwmon: (adm1275) Allow setting sample averaging

Current driver assume PWR_AVG and VI_AVG as 1 by default, and user needs
to set sample averaging via sysfs manually.

This patch parses the properties "adi,power-sample-average" and
"adi,volt-curr-sample-average" from device tree, and setting sample
averaging during probe. Input value must be one of value in the
list [1, 2, 4, 8, 16, 32, 64, 128].

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Link: https://lore.kernel.org/r/20220302123817.27025-2-potin.lai@quantatw.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/pmbus/adm1275.c b/drivers/hwmon/pmbus/adm1275.c
index d311e0557401c9e2456479704641f920efac68d6..3b07bfb43e93704677bfe57bed8c6d547789bd1d 100644 (file)
--- a/drivers/hwmon/pmbus/adm1275.c
+++ b/drivers/hwmon/pmbus/adm1275.c
@@ -475,6 +475,7 @@ static int adm1275_probe(struct i2c_client *client)
        int vindex = -1, voindex = -1, cindex = -1, pindex = -1;
        int tindex = -1;
        u32 shunt;
+       u32 avg;
 
        if (!i2c_check_functionality(client->adapter,
                                     I2C_FUNC_SMBUS_READ_BYTE_DATA
@@ -687,7 +688,7 @@ static int adm1275_probe(struct i2c_client *client)
                if ((config & (ADM1278_VOUT_EN | ADM1278_TEMP1_EN)) !=
                    (ADM1278_VOUT_EN | ADM1278_TEMP1_EN)) {
                        config |= ADM1278_VOUT_EN | ADM1278_TEMP1_EN;
-                       ret = i2c_smbus_write_byte_data(client,
+                       ret = i2c_smbus_write_word_data(client,
                                                        ADM1275_PMON_CONFIG,
                                                        config);
                        if (ret < 0) {
@@ -756,6 +757,43 @@ static int adm1275_probe(struct i2c_client *client)
                return -ENODEV;
        }
 
+       if (data->have_power_sampling &&
+           of_property_read_u32(client->dev.of_node,
+                                "adi,power-sample-average", &avg) == 0) {
+               if (!avg || avg > ADM1275_SAMPLES_AVG_MAX ||
+                   BIT(__fls(avg)) != avg) {
+                       dev_err(&client->dev,
+                               "Invalid number of power samples");
+                       return -EINVAL;
+               }
+               ret = adm1275_write_pmon_config(data, client, true,
+                                               ilog2(avg));
+               if (ret < 0) {
+                       dev_err(&client->dev,
+                               "Setting power sample averaging failed with error %d",
+                               ret);
+                       return ret;
+               }
+       }
+
+       if (of_property_read_u32(client->dev.of_node,
+                               "adi,volt-curr-sample-average", &avg) == 0) {
+               if (!avg || avg > ADM1275_SAMPLES_AVG_MAX ||
+                   BIT(__fls(avg)) != avg) {
+                       dev_err(&client->dev,
+                               "Invalid number of voltage/current samples");
+                       return -EINVAL;
+               }
+               ret = adm1275_write_pmon_config(data, client, false,
+                                               ilog2(avg));
+               if (ret < 0) {
+                       dev_err(&client->dev,
+                               "Setting voltage and current sample averaging failed with error %d",
+                               ret);
+                       return ret;
+               }
+       }
+
        if (voindex < 0)
                voindex = vindex;
        if (vindex >= 0) {